Combined analysis and validation of Earth rotation models and observations
Final Report Abstract
Within the six-year period of this Research Unit at GIH reliable consistent time series for Earth rotation parameters (ERP), geophysical excitation functions and low-degree spherical harmonic gravity field coefficients (GFC) have been determined for the first time due to their physical connection by the Earth's tensor of inertia. At DGFI within the project P6 (first three-year period) and P9 (last three-year period) of the Research Unit for the first time several polar motion excitation mechanisms are determined by combining precise geometic, gravimetric and altimetric space observations. The new improved findings about the individual contributions of the subsystems of the Earth to Earth rotation variations can be used to improve the understanding of geophysical processes and interactions. During the three-years period of the second phase of the Research Unit at IAPG an improved value for the complex Love number k2 has been determined by an inversion of the Earth system model DyMEG. This way the pole-tide Love number k2 has been estimated for the first time from precise geodetic observations instead of geophysical models. The results of P9 provide a considerable contribution to the understanding of geophysical processes and interactions in the Earth system and also to various goals of the research unit. Consistent time series of ERP and GFC, accurate time series of individual excitation mechanisms of the Earth rotation and physical Earth parameters will significantly improve the data base and quality (goal Z6). This project contributes to the field of Earth system science in general and corresponds with the goals of the Global Geodetic Observing System (GGOS; goal Z5). The findings of this project can be used to improve the modelling of geophysical processes in the relevant subsystems of the Earth and their interactions (goal Z1).
Publications
- (2008): Combined Analysis of Earth Orientation Parameters and Gravity Field Coefficients for Mutual Validation, in: Sideris, M.G. (eds.), Observing our Changing Earth, IAG Symposia, 133, 853-859, Springer
Heiker, A., Kutterer, H., Müller, J.
- (2008): Contribution of non-tidal oceanic mass variations to polar motion determined from space geodesy and ocean data, in: Sideris, M.G. (eds.), Observing our Changing Earth, IAG Symposia, 133, 439-445, Springer
Göttl, F. and F. Seitz
- (2010): Erdrotation und geophysikalische Anregungsmechanismen, Zeitschrift für Vermessungswesen, 135, Heft 2
Schmidt M., D. Angermann, M. Bloßfeld, F. Göttl, B. Richter, M. Seitz
- Integration of observations and models in a consistent least squares adjustment model, in: Kutterer, H., Seitz, F., Schmidt, M., Alkhatib, H., (eds.), 1st International Workshop on Quality of Geodetic Observation and Monitoring Systems (QuGOMS) 2011, IAG Symposia 141, Springer
Heiker, A., Kutterer, H.
- (2012): Combination of gravimetric and altimetric space observations for estimating oceanic polar motion excitations, Journal of Geophysical Research, 117, C10022
Göttl, F., M. Schmidt, R. Heinkelmann and R. Savcenko
(See online at https://doi.org/10.1029/2012JC007915) - (2012): Determination of the Earth’s Pole Tide Love Number k2 from Observations of Polar Motion Using an Adaptive Kalman Filter Approach, Journal of Geophysical Research, 117, B09403
Seitz, F., Kirschner, S., Neubersch, D
(See online at https://doi.org/10.1029/2012JB009296) - (2012): Stabilization of Satellite Derived Gravity Field Coefficients by Earth Rotation Parameters and Excitation Functions, in: Kenyon, S. Pacino, M., Marti, U. (eds.), Geodesy for Planet Earth, IAG Symposia, 136, 537-544, Springer
Heiker, A., Kutterer, H., Müller, J.
- (2014): Recursive adjustment approach for the estimation of physical Earth parameters from polar motion, in: Rizos, C., Willis, P. (eds.) Earth on the Edge: Science for a Sustainable Planet, IAG Symposia, 139, 453-460, Springer
Kirschner, S., Seitz, F.
(See online at https://doi.org/10.1007/978-3-642-37222-3_60) - (2014): Towards the combination of data sets from various observation techniques, in: Kutterer, H., Seitz, F., Schmidt, M., Alkhatib, H., (eds.), 1st International Workshop on Quality of Geodetic Observation and Monitoring Systems (QuGOMS) 2011, IAG Symposia 141, Springer
Schmidt, M., F. Göttl and R. Heinkelmann
(See online at https://doi.org/10.1007/978-3-319-10828-5_6)